Photocopying machine having removable modules

ABSTRACT

A copying apparatus is contained within a housing and includes a charging unit, a surface element for positioning individual sheets of copying paper in an exposure station, and a developing device containing developing media. A number of pairs of rollers are positioned in the housing for conveying individual sheets of copying paper through the copying apparatus. The housing includes a number of openable covers, preferably hinged to the housing, for gaining access to the interior of the apparatus. Each pair of rollers has one driven roller secured within the housing and the other roller is movably mounted within the housing. Relative to the housing, the driven rollers are spaced inwardly from the movably mounted rollers. By opening the covers on the housing, the charging units, surface element and developing device can be removed from the housing along with the movably mounted rollers associated with them for affording access to the driven rollers. The path of the copying paper through the housing has a U-shaped configuration with the legs of the U extending horizontally. By opening the covers in the housing and removing the associated parts inwardly of the cover, it is possible to gain access to the different portions of the path of the copying paper.

United States Patent Cranskens et al.

PHOTOCOPYING MACHINE HAVING REMOVABLE MODULES [72] Inventors: Georg Cranskens, Wedel/l-lolstein;

- Gunther Krober, Hamburg-Rah]- stedt; Richard Palm, Hamburg, all of Germany [73] Assignee: Lumoprint Zindler KG, Hamburg,

Germany [22] Filed: April 23, 1969 [21] Appl. No.: 818,522

[30] Foreign Application Priority Data April 26, 1968 Germany ..P 17 72 296.2

[52] U.S. Cl ..355/3, 355/11 [51] Int. Cl. ..G03g 15/00 [58] Field of Search ..355/3, 10, 50, 64, 97

[ 56] References Cited UNITED STATES PATENTS v 3,512,884 5/1970 Murgas et a1 ..3S5/51 3,552,849 l/l971 Limberger ..355/l4 3,547,536 12/1970 Phleps et a1. ..355/50 2,435,099 1/1948 Pratt et a1. ..355/64 3,180,239 4/1965 Shearer et al ..355/3 X 3,352,218 11/1967 Ostensen ..'35'5/3 [451 Oct. 17, 1972 Primary Examiner-Samuel S. Matthews Assistant Examiner-Kenneth C. Hutchison Attorney-McGlew and Toren [57] ABSTRACT A copying apparatus is contained within a housing and includes a charging unit, a surface element for positioning individual sheets of copying paper in an exposure station, and a developing device containing developing media. A number of pairs of rollers are positioned in the housing for conveying individual sheets of copying paper through the copying apparatus. The housing includes a number of openable covers, preferably hinged to the housing, for gaining access to the interior of the apparatus. Each pair of rollers has one driven roller secured within the housing and the other roller is movably mounted within the housing. Relative to the housing, the driven rollers are spaced inwardly from the movably mounted rollers. By opening the covers on the housing, the charging units, surface element and developing device can be removed from the housing along with the movably mounted rollers associated with them for affording access to the driven rollers. The path of the copying paper through the housing has a U-shaped configuration with the legs of the U extending horizontally. By opening the covers in the housing and removing the associated parts inwardly of the cover, it is possible to gain access to the different portions of the path of the copying paper.

7 10 Claims, 12 Drawing Figures PATENTEOHBI 17 1972 SHEET 1 BF 5 ATTORNEYS 3.698.804 SHEET 0F 5 I PATENTEDucI 171972 fiwzz R lwnlillulllliillliltll\ m Eu PHOTOCOPYING MACHINE HAVING REMOVABLE MODULES DESCRIPTION In copying apparatus the path taken by the paper through the various devices or past the same is determined by pairs of transport rollers and guide elements. ln order to achieve a perfect exposure of the matter contained in an original, passing along the exposure plate, the copying material must be applied with absolute precision to an exposure platform, forming part of the exposure device and arranged inside the apparatus. The velocities of the original and of the sheet of copying paper must match accurately to achieve a perfect and distortion-free transfer of the picture. For this reason these apparatus, and more particularly apparatus for manufacturing copies by photo-electric means according to the invention, present the particular problem of producing a high precision paper travel. Whilst all structural units may be fixed in the housing and be functionally controlled, a sheet of copying paper is guided through the paper travel. However, breakdowns may occur, particularly with large numbers of copies and high working speeds, for example due to a corner of the sheet buckling or due to other effects caused by the nature of the paper. In order to avoid long standstill times for these apparatus, e.g. through waiting for a maintenance engineer, these apparatus present the special problem of rendering the whole length of the travel of the sheet of paper accessible.

The solution of this problem presents certain difficulties because the sheet of paper passes past some of the processing units, whilst in another part of the apparatus it travels through the processing units. It also must be taken into consideration that, particularly in apparatus based on the electro-photographic method, these units may be rather complicated, and the charging device is provided with high voltage terminals. Between the processing units there are arranged pairs of transport rollers which, if they are fixed in the housing, prevent access from an open housing side to the guide elements behind them.

lt has already been proposed to render an apparatus altogether openable to provide access to at least certain parts of the paper travel. This leads to a complicated construction of the frame for the processing units and, in order to achieve an accurate reproduction, to the use of a so-called surface exposure device on which the original is stationary. The problem becomes particularly difficult where the original is processed whilst moving because here the accurate synchronization between original and copying paper becomes essential, particularly where the apparatus is to be compact, i.e. of small dimensions. In this case the openable arrangement of the frame forms a disadvantage because the parts must be arranged in a certain manner and play in the bearings may lead to inaccuracies where the original is exposed in a continuous manner.

It is an object of the invention to provide a copying apparatus which operates according to the continuous method, which has small dimensions and may be easily operated by untrained operators, whilst giving access to all sections of the paper travel in cases of breakdowns.

According to the invention, this object is realized in that with regard to the transport means the paper travel LII is rendered accessible by means of the drawer-like or flap-like construction and arrangement of all units arranged therein or thereon, whilst at least one roller of several pairs of transport rollers is fixed in the housing.

In this manner the frame may be made in one part and the precision of the mutual arrangement of the unit is assured whilst the detachable arrangement of individual units renders some or all sections of the paper travel accessible, but the fixed arrangement of a driven roller of a pair of transport rollers ensures simultaneously the accurate positioning and actuation of the detachable units after their insertion.

In the preferred embodiment of the invention the paper travel inside the housing has substantially the shape of a U lying on its side, of which one leg extends parallel to the upper side of the housing and starts with the stack holder arranged thereunder, whilst a vertical, center section of the U shaped travel contains a structural element with rollers and possibly a picture platform, and the lower leg of the U shaped travel contains the developing device and the fusing device in front of a delivery arrangement with transport rollers.

This arrangement makes possible an advantageous compact construction with a part of the exposure channel extending between the legs, whilst the paper travel extends always within the zone of parts of the housing walls or of the housing bottom.

Preferably the housing cover plate is adapted to be opened after the manner of a flap above the switching means and the charging device, and the end face of the housing, alongside which the center section of the U shaped travel is arranged, has a door. It should be mentioned that the housing surrounds the frame.

In a particularly preferred embodiment of the invention, the switching means and the charging device are constructed as box-shaped modules and mounted detachable in profiles open towards the top, wherein the modules have at least in one end wall resiliently actuated contact members which engage fixed contacts in an assembly wall when the module is fitted. In this way even modules operated under high voltage can be freely extracted and are automatically separated on extraction. The switching off takes place already when the housing is opened, by means of a safety switch in the circuit. No special contact connections need be made during the fitting because the connections are automatically closed by the contact members. In addition, this arrangement ensures the correct insertion since otherwise the connections are not established.

Preferably, the unit associated with the platform is fixed detachably by a tensioning device and may be withdrawn in the direction parallel to the legs of the U- shaped travel. It is here an advantage that this module is arranged behind a door on the vertical section of the U-shaped travel. It should be taken into consideration that this unit of the platform also comprises pairs of transport rollers wherein preferably the movement of the movable unit is perpendicular to the movement of the copying sheet. Preferably, the mounting walls have centering profiles and the unit corresponding mating profiles extending in the direction of extraction and both sides of the unit are provided with holdinglevers with bent arms adapted to engage behind pins on the mounting walls and/or the associated part of the platform. To ensure a sufficiently tight seat and mutual engagement of the transport rollers associated in pairs, the arms have preferably wedge-shaped working surfaces. The invention also includes an elastic construction of the arms and a bend such that the levers pass beyond dead center when the closure is made. In this way, the withdrawable module is automatically secured. Obviously, in view of the centering profiles, the levers serve only as fixing means and the resulting forces can have no effect in a translatory displacement of this unit.

Preferably, the developing device is mounted as a drawer-like unit with its inlet under the platform and may be withdrawn as a whole after opening the door wherein a pair of transport rollers associated with a platform unit forms the inlet roller pair into the developing device and behind its outlet under a downwardly offset step there is arranged a further pair of transport rollers acting as outlet rollers. By means of this arrangement of the pair of rollers, at least one part of each pair of rollers is fixed in the housing and the exact travel path is ensured even with detachable parts.

These apparatus present a particular problem in the removal of the heat generated in the fusing device. Generally a blower is arranged in this zone. Since the fusing device is behind the developing device, i .e., adjacent thereto, precautions must be made to prevent the developing device from being heated excessively, because a latent picture may be weakened by the action of heat. For this reason, known devices have labyrinths or substantial gaps at this point. At any rate, the arrangement of a partition is desirable but this affects the accessability. The invention, therefore, comprises also a pivotable partition between a chamber for the developing device and the delivery device with at least one pair of transport rollers, wherein the partition forms a guide element between the pair of transport rollers at the outlet of the developing device and the lower pair of transport rollers of the delivery device and wherein the partition is pivotable about hinges. By means of this guide element mounted diagonally to the run of the paper, a good insulation of the chamber with the developing device is achieved. Preferably, a flow of cooling air flows through the intermediate space. After withdrawing the developing device module, the pivotability makes it possible to reach through the free space into further transport means in the zone of the fusing device.

Preferably, the partition consists of two wall sections of which one extends obliquely as guide element over the entire width of the guide path, and has in its upper zone an arm directed towards the developing device, whilst the other wall section forms a hinged defining wall for the chamber of the developing device and is a supporting element of smaller width, the upper end of which has a recess adapted to receive the arm of the other wall section. In this manner, the section forming the guide element can be raised and the other wall section can be lowered, enabling the first section to be folded over. A defined position is achieved in that the wall section acting as guide element has a hinge above its lower edge and the mating hinge is provided on a raised portion of the housing bottom which continues in an oblique section corresponding to the position of the raised wall section.

According to an essential feature of the invention, the delivery device is a plug-in plate adapted to be pulled out at the end of the leg of the U-shaped path through a hole in the housing, and a freely revolving roller of the at least one pair of transport rollers of the delivery device is so arranged on the plug-in plate that in the plugged in position of the plate it makes contact with a driven transport roller firmly mounted in the housing. This ensures the precision of the transport arrangements, facilitates their drive by rollers fixed in the housing or frame, whilst enabling the arrangement to be such that in this particular position where blockages may occur the complete opening of the apparatus may be easily achieved. To this end there are arranged, in the region of the delivery device, on both sides of the housing or on supporting walls extending parallel to the side walls of the housing, at least two supporting rollers, the angled flanges of which guide the plug-in plate; a spring loaded pawl is mounted on at least one side of the delivery slot and its locking element overlies a side web. In this manner the plug-in plate is fixed in an easily detachable manner. Furthermore, the side webs may have at the bottom guide grooves open towards the center and retaining a withdrawable slide. This enables a trough to be mounted for receiving the copies, whilst this trough can be pushed back into the apparatus when not in use.

The invention will be further described, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 is a diagrammatical side elevation of the copying apparatus in cross-section, indicating the association of the parts and the paper travel;

FIG. 2 is an end elevation of FIG. I viewed from the left with open end side;

FIG. 3 is a plan view of the left part in FIG. 1;

FIG 4 is a view in perspective of a charging device in the form of a module;

FIG. 5 is a partial view of an assembly wall associated with the module of FIG. 4;

FIG. 6 shows another module in a view corresponding to that of FIG. 4;

FIG. 7 shows an assembly wall associated with the module of FIG. 6 in a view corresponding to that of FIG. 5;

FIG. 8 is a partial side elevation of FIG. 1, showing the withdrawable module at the platform on an enlarged scale;

FIG. 9 is a front elevation of the partition arrangement between the chamber for the developing device and the delivery arrangement;

FIG. 10 is a side elevation of this partition;

FIG. 11 is an end elevation of the delivery arrangement as viewed in FIG. 1 from the left on the lower section of the end wall of the housing;

FIG. 12 is a cross-section along the line XII-XII in FIG. 11.

The apparatus of FIG. 1, has a housing with a top cover 1, two end faces 2, 3 and a bottom 4. The side walls extend parallel to the plane of the drawing. Near the end wall 3, an exposure plate 5 is mounted in an opening of the top cover 1. A substantially L-shape channel 6 extends from the exposure plate first downwardly and then to a picture platform 7. At least one exposure light source 9 is provided on the vertical section 8 of this channel. A deflecting mirror 10 is located in the angle and an objective lens 127 may be provided.

In front of and behind the exposure plate 5, transport rollers l1, 12 mounted rotatably in the housing or in the frame project towards the top through slots in the top cover 1 and serve to guide an original over the exposure plate 5. These rollers l1, 12 are rotatively driven by a device, mounted for example at 13, by means of transmission members.

The horizontal section of the channel 6 divides the apparatus, and the U-shaped paper travel extends around the section. The paper run starts with a stack holder 14 adjacent to the vertical section 8 of the channel 6. At the delivery end of the stack holder containing a stack of sheets of copying paper, there is a group of rollers with a withdrawing roller 15 and an arrangement of transfer rollers 16. One of the rollers is resiliently mounted enabling the rollers to be pushed apart. This unit which also comprises a switch 17 located downstream of the transfer rollers 16 has'already been described in the applicants co-pending US. application Ser. No. 726,638, now US. Pat. No. 3,552,849.

A charging device 18 is mounted behind the switch or switching means. Then follow arcuate guide elements 19,20 which guide the paper travel to the exposure platform 7. The latter comprises a unit 21 with a surface element 22. This element and the platform 7 are provided with pairs of transport rollers 23, 24 and 25, 26 at the inlet and outlet and extend substantially vertically. Under the pair of transport rollers 25, 26 there is the inlet to the development section, shown generally at 27 and comprising an arcuate guide element 28 on which the sheet of copying paper passes to an outlet 29, as known per se. Downstream thereof and partly in the zone of a downwardly extending step 30, there is a pair of transport rollers 31, the lower roller of which is movable downwardly flexibly, so that the gap between the rollers can widen. To this end, the roller mounting is provided with a ratchet engagement which can be adjusted so that the lower roller can be withdrawn and the paper run is fully accessible also at this point.

The developing section is defined towards the center of the apparatus by a partition 32. It is also located on the bottom 4 in guides parallel to the plane of the drawing. A friction wheel 33 is mounted on the upper side of the developing section engaging a driven roller 34, and actuating a pump in the developing section. The roller 34 may be mounted vertically movably by means of a spring 36 on a partition 124 which may define the channel 6. The guides have recesses into which engage projections in the bottom of the developing device 27 when the same is pushed in fully, i.e. until it abuts on the wall 32. The wall 32 comprises a partition arrangement indicated generally at 35 and having hinged sections 36, 37, described further below with reference to FIGS., 9 and 10. A fixed guide element 38 extends obliquely downwardly, parallel to the wall section 37 and serves also as air guide for the air coming from the fan 39. A fusing device 40 is provided in front of the fan.

The delivery device 41 comprises also the plug-in plate 42, described in detail with reference to FIGS. 11

correct fitting establishes contact. FIG. 2 shows the v and 12, and the pairs of transport rollers 43, 44 and 45, 46. The rollers 44, 46 are freely revolving rollers arranged on the plate 42, whilst the rollers 43, 45 are mounted in the housing or or in the frame and are driven rollers. Similarly, the rollers 24 and 26 are driven, and the associated rollers 23 and 25 are freely rotatable.

Within the region of the delivery orifice or slot 41, the housing end wall 3 has an opening 47, the height of which is such that the plug-in plate 42 and its associated rollers 44, 46 can be withdrawn. Preferably, the bottom 4 is recessed underneath the plug-in plate 42.

The whole end wall 2 is constructed after the manner of a door, adapted to be opened about a hinge 48 in the direction of the arrow 49. Also the top cover 1 is adapted to be opened, at least in the zone above the parts 14 18; it may be constructed in the form of two flaps 54, 55, adapted to be opened in the direction indicated by arrows 52, 53 about hinges 50, 51, thus rendering accessible the associated parts of the paper travel.

It should be mentioned that the rollers 23, 25, and 44, 46 are adapted to be withdrawn with the associated unit modules.

FIGS. 2 and 3 show the housing side walls 56, 57 and the frame or mounting walls 58, 59 arranged at spaced relationship therefrom.

In FIGS. 2 and 3, the housing above the parts 15 18 is shown open, as well as the door forming the end wall 2. Electrical connecting means 130 and mounting and driving means, e.g., transmissions 131, are arranged between the mounting walls. Drive shafts, rollers, and the like extend through the mountings in the frame walls into the drive mechanisms.

Referring now to FIGS. 4 7, the switching means shown in FIG. 6 are arranged on a box-shaped module 60, the length of which is such that it fits exactly between the frame walls 58, 59. These walls have at this point U-shaped profiles 61 (FIG. 3 and FIG. 7) and 62 (FIG. 3), adapted to receive the box-shaped module 60, the top of which may be equipped with a handle 63. The switch 64, associated with the actuating member 65 which extends into the path of the paper is connected by leads 66, 67 to contact members 69, 70, resiliently projecting from the end face 68 of the module (see 127 in FIG. 3). Corresponding contact members 71, 72 are provided on the frame wall and make contact with the resilient contact members 70,69 when the module is plugged in from the top.

Similarly, the charging section is constructed as a box-shaped housing or module 73 and has a handle 74 on its top. Charging wires 76, 77 may be arranged in this box-shaped unit above and below a passage for the copying material; these wires terminate in contacts 78, 79 and 80, 81, respectively. Also these contact members are mounted resiliently in the end wall of the box-shaped housing 73. Corresponding to the dimensions of the housing 73, the frame walls 58, 59 carry upwardly open plug-in rails 82, 83. In the zone of the rails 82, for example, there are mating contacts 83, 84 and 85, 86, which make contact with the box contacts, when the charging device is plugged in, so that only module 73 in the withdrawn state, with the fixed contacts 84, 86, and the spring mounting of the resilient contacts 79, 81, supported by springs 87, 88. Obviously, also the fixed contacts 83 to 86 and 71, 72 could be spring mounted, whilst the contacts on the withdrawable section could be fixed.

FIG. 8 shows the exposure platform 7 with the rollers 24, 26 fixed in the housing. However, the platform 7 may also be combined with the module 21 and withdrawable in conjunction therewith. In this case, the whole unit is mounted as follows. Pins 90, 91 are arranged on the frame walls. The unit 21 with the element 22 has, for example, in the side walls a slot 89 extending parallel to the long axis of the apparatus. The pins 90, 91 engage into these slots and ensure the perfect vertical alignment when the module 21 is pushed against the platform 7. Retaining levers 92 are pivotable about pivots 93, 94 on the module 21 in the side walls, such as 98 in FIG. 8. These levers have angled arms 95 which engage behind pins 96 located either on the frame walls or on parts of the platform 7.

It may be seen from FIG. 8 that, when the lever 92 is pivoted in a clockwise direction, as viewed in FIG. 8, the arms 95 disengage from behind the pins 96 and the module 21 can be withdrawn towards the left, thus giving access to the paper run. During the insertion, the pins 90 engage into the slots 89 and the levers 92, 97 are pivoted in an anticlockwise direction; this causes the arms 95 to tighten the module 21 so by virtue of their profile that the rollers 23, 25 are pressed against their associated rollers 24, 26. Preferably, the guide element 19 forms part of the unit 21.

The partition arrangement 35 will now be described with reference to FIGS. 9 and 10. It may be seen that the section 36 has, for example, only half the width of the wall section 37, forming the guide. Near its upper end, the wall section 37 has an arm 99 the edge 100 of which, facing the developing section 27, is angled downwardly. This edge has a recess .101. Into this recess engages an angled portion 102 of the wall section 36. By gripping the section 37 adjacent to the section 36, the former can be slightly pivoted about the hinge 103 in a clockwise sense, freeing the edge 100 from the section 36 which pivots about the hinge 104 into the developing chamber, permitting the wall section 37 to be folded down.

Preferably, the hinge 104 is arranged to the right side of the wall 32 which has a recess through which extends an angled, lower, part 105 of the wall section. In this manner, the wall section 36 drops automatically into the folded position, when the section 37 is raised.

The bottom 4 has preferably a raised portion 126 between the wall sections, with the hinge 103 arranged at its end. The downwardly extending web 106 serves as abutment for the lower end of the wall section.

As may be seen from FIG. 2, the developing device has raised bottom portions 107, 108 which are adapted to be pushed on to the guides 109, 110 on the bottom 4.

As may be seen from FIGS. 11 and 12, freely rotatable rollers 111, 112 are arranged at the bottom of the housing walls 57, 58, namely behind the opening 47 as viewed in FIG. 1; thus, three rollers 11, 113, 114 may be arranged on either side, one behind the other. The plug-in plate 42 has on the top outwardly angled flanges 115, 116, the horizontal legs 117, 118 of which run on the said rollers 111 to 114. Thus, the flanges 115, 116 may form below the surface of the plug-in plate 42 guide grooves 119, 120, open towards the center, and a withdrawable slide 121 in mounted therein. The rollers 44, 46, described already in connection with FIG. 1 are mounted freely rotatably on the flanges 115, 116 and are adapted to be withdrawn with the plug-in plate and make contact with the driven rollers 43, 45, when the plug-in plate is inserted. The inserted position may be secured, for example, by a spring-loaded pawl 122 arranged on the side wall 58 immediately behind the opening 47. The locking element 123 engages, for example, in front of the leg 118 of the side flange 116. A handle 123 protruding from the housing at 122 is accessible through the opening 47 and makes it possible to withdraw the plug-in plate.

It may thus be seen that the elements 17, 18, 19, 23, 21, 25, 27, as well as 41, 44, 46 are, in fact, withdrawable and that the partition 35 is adapted to be folded so that the lower part of the housing, in the region of the fusing device 40, is accessible from both sides. Also the roller arrangement 15, 16 and the stack holder 14 are easily accessible through the flap 55, which is important for placing the sheets of copying paper in position. It may also be seen that the elements 15, 16, 24, 7, 26, 31, 43, 45, necessary to ensure the positive guiding action, remain fixed and can be actuated in synchronism with the transport means 11, 12 for the original.

We claim:

1. A copying apparatus including a housing; a charging device, an exposure device including an exposure plate for an original accessible on the outer surface of said housing and a unit including an exposure platform and a surface element cooperating with said exposure platform for positioning individual sheets of copying paper in an exposure station formed in said exposure device, a developing device with developing media, a fusing device, a stack holder for a stack of sheets of copying paper, and a delivery device for discharging developed sheets of copying paper from said housing being located within said housing; transport means within said housing forming a path of travel for conveying individual sheets of copying paper from said stack holder through said charging device, exposure device, developing device and fusing device to said delivery device; switching means for controlling said charging device, exposure device, fusing device and transport means and including actuating members adapted to be operated by an original passing over said exposure plate; wherein the improvement comprises that said housing comprises a plurality of openable covers for gaining access to the interior of said housing, said transport means comprising a number of pairs of rollers spaced along the path of travel of the sheets of copying paper within said housing, each said pair of rollers comprising a first roller and a second roller, each of said first rollers being secured within said housing and being spaced inwardly relative to its corresponding said second roller from the adjacent said openable cover in said housing; means within said housing for driving said first rollers; each of said second rollers being freely rotatable and movably mounted within said housing for displacement from the path of travel of the copying paper through said housing; said charging unit, surface element and developing device being separately removable through openings closed by said covers along with said second rollers so that access to the path of paper travel is attainable without removing said first rollers, a partition in said housing between a chamber for said developing device and said delivery device, mounting means provided in said housing for said partition arrangement, wherein the said partition arrangement is pivotable on said mounting means and forms a guide element from the outlet of said developing device to a lower pair of transport rollers.

2. A copying apparatus as set forth in claim 1, wherein the partition consists of two sections which are interconnected detachably by means of interengaging elements and retain one another in the engaged position, whilst in the release position they are foldable, one element forming the guide member and the other, narrower element forming a support, and the hinge-like mounting means are arranged on the wider section along its bottom edge and on a raised part of the housing bottom, which raised portion has an oblique section which continues the said wider wall section when it is in its erected position.

3. A copying apparatus including a housing; a charging device, an exposure device including an exposure plate for an original accessible on the outer surface of said housing and a unit including an exposure platform and a surface element cooperating with said exposure platform for positioning individual sheets of copying paper in an exposure station formed in said exposure device, a developing device with developing media, a fusing device, a stack holder for a stack of sheets of copying paper, and a delivery device for discharging developed sheets of copying paper from said housing being located within said housing; transport means within said housing forming a path of travel for conveying individual sheets of copying paper from said stack holder through said charging device, exposure device, developing device and fusing device to said delivery device; switching means for controlling said charging device, exposure device, fusing device and transport means and including actuating members adapted to be operated by an original passing over said exposure plate; wherein the improvement comprises that said housing comprises a plurality of openable covers for gaining access to the interior of said housing, said transport means comprising a number of pairs of rollers spaced along the path of travel of the sheets of copying paper within said housing, each said pair of rollers comprising a first roller and a second roller, each of said first rollers being secured within said housing and being spaced inwardly relative to its corresponding said second roller from the adjacent said openable cover in said housing; means within said housing for driving said first rollers; each of said second rollers being freely rotatable and movably mounted within said housing for displacement from the path of travel of the copying paper through said housing; said charging unit, surface element and developing device being separately removable through openings closed by said covers along with said second rollers so that access to the path of paper travel is attainable without removing said first rollers, the path of paper travel provided by said transport means has a U-shaped configuration with the legs of said U extending horizontally and the connecting web extending vertically, the upper leg of said U- shaped path of travel extending from said stack holder toward one end wall of said housing, the connecting web extending downwardly from said upper leg and adjacent said one end wall of said housing and the lower leg of said path of travel extending from the connecting web toward the other end wall of said housing to said delivery device, one of said covers being positioned in said housing above and adjacent to the upper leg of said U-shaped path of travel and said charging device and switching means being located aligned below the opening closed by said cover so that said charging device and switching means are accessible and removable through the opening, guide and abutment means being secured within said housing and being open at the upper ends thereof for supporting and securing said charging device and switching means within said housing, said one end wall of said housing adjacent the connecting web of said U-shaped path of travel having an opening therein closed by another of said covers which is hinged to said housing, said surface element of said exposure device being positioned adjacent said end wall and being removable through said hinged cover therein, means associated with said surface element for releasably engaging said surface element with said exposure platform, said unit including said exposure platform comprises locking members, cooperating elements for said locking members positioned adjacent said exposure platform, guide means provided in conjunction with said locking members on the walls of said housing which extend in the direction of the legs of the U-shaped path of travel of the copying paper, and a unit module including said surface element being supported and held within said housing by said guide means with said locking members and cooperating elements securing said surface element in position adjacent said exposure platform and being withdrawn from said housing through said one end wall thereof adjacent the vertically arranged portion of said U-shaped path of travel.

4. A copying apparatus, as set forth in claim 3, characterized in that the walls for mounting said unit module including said surface element having centering profiles thereon and said unit module having corresponding mating profiles which extend in the direction of withdrawal of said unit module, and both sides of said unit module being provided with retaining levers with angled arms, and the walls mounting said unit module being provided with pins with which these angled arms cooperate by pivoting to lock said surface element in place.

5. A copying apparatus as set forth in claim 4, wherein said arms have a wedge-shaped working surface and are of elastic construction, and are angled so that, when the closure is made, the levers pass beyond a dead center position.

6. A copying apparatus including a housing; a charging device, an exposure device including an exposure plate for an original accessible on the outer surface of said housing and a unit including an exposure platform and a surface element cooperating with said exposure platform for positioning individual sheets of copying paper in an exposure station formed in said exposure device, a developing device with developing media, a fusing device, a stack holder for a stack of sheets of copying paper, and a delivery device for discharging developed sheets of copying paper from said housing being located within said housing; transport means within said housing forming a path of travel for conveying individual sheets of copying paper from said stack holder through said charging device, exposure device, developing device and fusing device to said delivery device; switching means for controlling said charging device, exposure device, fusing device and transport means and including actuating members adapted to be operated by an original passing over said exposure plate; wherein the improvement comprises that said housing comprises a plurality of openable covers for gaining access to the interior of said housing, said transport means comprising a number of pairs of rollers spaced along the path of travel of the sheets of copying paper within said housing, each said pair of rollers comprising a first roller and a second roller, each of said first rollers being secured within said housing and being spaced inwardly relative to its corresponding said second roller from the adjacent said openable cover in said housing; means within said housing for driving said first rollers; each of said second rollers being freely rotatable and movably mounted within said housing for displacement from the path of travel of the copying paper through said housing; said charging unit, surface element and developing device being separately removable through openings closed by said covers along with said second rollers so that access to the path of paper travel is attainable without removing said first rollers, the path of paper travel provided by said transport means has a U-shaped configuration with the legs of said U extending horizontally and the connecting web extending vertically, the upper leg of said U- shaped path of travel extending from said stack holder toward one end wall of said housing, the connecting web extending downwardly from said upper leg and adjacent said one end wall of said housing and the lower leg of said path of travel extending from the connecting web toward the other end wall of said housing to said delivery device, one of said covers being positioned in said housing above and adjacent to the upper leg of said U-shaped path of travel and said charging device and switching means being located aligned below the opening closed by said cover so that said charging device and switching means are accessible and removable through the opening, guide and abutment means being secured within said housing and being open at the upper ends thereof for supporting and securing said charging device and switching means within said housing, said one end wall of said housing adjacent the connecting web of said U-shaped path of travel having an opening therein closed by another of said covers which is hinged to said housing, said surface element of said exposure device being positioned adjacent said end wall and being removable through said hinged cover therein, means associated with said surface element for releasably engaging said surface element with said exposure platform, said developing device is a drawershaped unit module arranged with its inlet below the exposure platform, guide means are provided in said housing extending in the direction towards said cover through which said developing device is movable, and a roller arranged on the said unit module and a roller arranged on the platform form a pair of transport rollers leading into said developing device, and said developing device has outlet means downstream of which a pair of outlet transport rollers is arranged within said housing, and said developing device has a downwardly offset step behind said outlet means and one roller of said pair of outlet transport rollers is located within the said step. v

7. A copying apparatus as set forth in claim 6, wherein the apparatus contains a partitioning wall above the developing device, mounting means withsprings being provided on the said partitioning wall carrying a roller, wherein the upper side of the developing device carries a friction wheel and driving means of the apparatus drive through transmission means the said roller and support with the said friction wheel the insertion of the developing device.

8. A copying apparatus including a housing; a charging device, an exposure device including an exposure plate for an original accessible on the outer surface of said housing and a unit including an exposure platform and a surface element cooperating with said exposure platform for positioning individual sheets of copying paper in an exposure station formed in said exposure device, a developing device with developing media, a fusing device, a stack holder for a stack of sheets of copying paper, and a delivery device for discharging developed sheets of copying paper from said housing being located within said housing; transport means within said housing forming a path of travel for conveying individual sheets of copying paper from said stack holder through said charging device, exposure device, developing device and fusing device to said delivery device; switching means for controlling said charging device, exposure device, fusing device and transport means and including actuating members adapted to be operated by an original passing over said exposure plate; wherein the improvement comprises that said housing comprises a plurality of openable covers for gaining access to the interior of said housing, said transport means comprising a number of pairs of rollers spaced along the path of travel of the sheets of copying paper within said housing, each said pair of rollers comprising a first roller and a second roller, each of said first rollers being secured within said housing and being spaced inwardly relative to its corresponding said second roller from the adjacent said openable cover in said housing; means within said housing for driving said first rollers; each of said second rollers being freely rotatable and movably mounted within said housing for displacement from the path of travel of the copying paper through said housing; said charging unit, surface element and developing device being separately removable through openings closed by said covers along with said second rollers so that access to the path of paper travel is attainable without removing said first rollers, the path of paper travel provided by said transport means has a U-shaped configuration with the legs of said U extending horizontally and the connecting web extending vertically, the upper leg of said U- shaped path of travel extending from said stack holder toward one end wall of said housing, the connecting web extending downwardly from said upper leg and adjacent said one end wall of said housing and the lower leg of said path of travel extending from the connecting web toward the other end wall of said housing to said delivery device, one of said covers being positioned in said housing above and adjacent to the upper leg of said U-shaped path of travel and said charging device and switching means being located aligned below the opening closed by said cover so that said charging device and switching means are accessible and removable through the opening, guide and abutment means being secured within said housing and being open at the upper ends thereof for supporting and securing said charging device and switching means within said housing, said one end wall of said housing adjacent the connecting web of said U-shaped path of travel having an opening therein closed by another of said covers which is hinged to said housing, said surface element of said exposure device being positioned adjacent said end wall and being removable through said hinged cover therein, means associated with said surface element for releasably engaging said surface element with said exposure platform, said delivery device includes a plug-in plate fitted in said housing which is adapted to be pulled out to provide access to the lower leg of the U- shaped path of travel, and one of said second rollers of at least one pair of transport rollers is mounted in the region of the delivery device on said plug-in plate and at least one said fixed driven first roller is arranged on the housing so that in the inserted position of said plugin plate it makes contact with said second roller on said plug-in plate.

9. A copying apparatus as set forth in claim 8, comprising at least two support rollers located in the zone of said delivery device on both sides of said housing, and said plug-in plate has angled flanges guided on the said support rollers and at least one side of the opening from said delivery device is provided with a springloaded pawl having a locking element which engages in front of a side member of said housing at the opening.

10. A copying device as set forth in claim 9, wherein guide grooves, open towards the center are formed on the underside of the plug-in plate, with a withdrawable slide plate mounted therein, and wherein the plug-in plate forms in this zone the bottom of the open housing. 

1. A copying apparatus including a housing; a charging device, an exposure device including an exposure plate for an original accessible on the outer surface of said housing and a unit including an exposure platform and a surface element cooperating with said exposure platform for positioning individual sheets of copying paper in an exposure station formed in said exposure device, a developing device with developing media, a fusing device, a stack holder for a stack of sheets of copying paper, and a delivery device for discharging developed sheets of copying paper from said housing being located within said housing; transport means within said housing forming a path of travel for conveying individual sheets of copying paper from said stack holder through said charging device, exposure device, developing device and fusing device to said delivery device; switching means for controlling said charging device, exposure device, fusing device and transport means and including actuating members adapted to be operated by an original passing over said exposure plate; wherein the improvement comprises that said Housing comprises a plurality of openable covers for gaining access to the interior of said housing, said transport means comprising a number of pairs of rollers spaced along the path of travel of the sheets of copying paper within said housing, each said pair of rollers comprising a first roller and a second roller, each of said first rollers being secured within said housing and being spaced inwardly relative to its corresponding said second roller from the adjacent said openable cover in said housing; means within said housing for driving said first rollers; each of said second rollers being freely rotatable and movably mounted within said housing for displacement from the path of travel of the copying paper through said housing; said charging unit, surface element and developing device being separately removable through openings closed by said covers along with said second rollers so that access to the path of paper travel is attainable without removing said first rollers, a partition in said housing between a chamber for said developing device and said delivery device, mounting means provided in said housing for said partition arrangement, wherein the said partition arrangement is pivotable on said mounting means and forms a guide element from the outlet of said developing device to a lower pair of transport rollers.
 2. A copying apparatus as set forth in claim 1, wherein the partition consists of two sections which are interconnected detachably by means of interengaging elements and retain one another in the engaged position, whilst in the release position they are foldable, one element forming the guide member and the other, narrower element forming a support, and the hinge-like mounting means are arranged on the wider section along its bottom edge and on a raised part of the housing bottom, which raised portion has an oblique section which continues the said wider wall section when it is in its erected position.
 3. A copying apparatus including a housing; a charging device, an exposure device including an exposure plate for an original accessible on the outer surface of said housing and a unit including an exposure platform and a surface element cooperating with said exposure platform for positioning individual sheets of copying paper in an exposure station formed in said exposure device, a developing device with developing media, a fusing device, a stack holder for a stack of sheets of copying paper, and a delivery device for discharging developed sheets of copying paper from said housing being located within said housing; transport means within said housing forming a path of travel for conveying individual sheets of copying paper from said stack holder through said charging device, exposure device, developing device and fusing device to said delivery device; switching means for controlling said charging device, exposure device, fusing device and transport means and including actuating members adapted to be operated by an original passing over said exposure plate; wherein the improvement comprises that said housing comprises a plurality of openable covers for gaining access to the interior of said housing, said transport means comprising a number of pairs of rollers spaced along the path of travel of the sheets of copying paper within said housing, each said pair of rollers comprising a first roller and a second roller, each of said first rollers being secured within said housing and being spaced inwardly relative to its corresponding said second roller from the adjacent said openable cover in said housing; means within said housing for driving said first rollers; each of said second rollers being freely rotatable and movably mounted within said housing for displacement from the path of travel of the copying paper through said housing; said charging unit, surface element and developing device being separately removable through openings closed by said covers along with said second rollers so that access to the path of paper travel is attainable without removing said fIrst rollers, the path of paper travel provided by said transport means has a U-shaped configuration with the legs of said U extending horizontally and the connecting web extending vertically, the upper leg of said U-shaped path of travel extending from said stack holder toward one end wall of said housing, the connecting web extending downwardly from said upper leg and adjacent said one end wall of said housing and the lower leg of said path of travel extending from the connecting web toward the other end wall of said housing to said delivery device, one of said covers being positioned in said housing above and adjacent to the upper leg of said U-shaped path of travel and said charging device and switching means being located aligned below the opening closed by said cover so that said charging device and switching means are accessible and removable through the opening, guide and abutment means being secured within said housing and being open at the upper ends thereof for supporting and securing said charging device and switching means within said housing, said one end wall of said housing adjacent the connecting web of said U-shaped path of travel having an opening therein closed by another of said covers which is hinged to said housing, said surface element of said exposure device being positioned adjacent said end wall and being removable through said hinged cover therein, means associated with said surface element for releasably engaging said surface element with said exposure platform, said unit including said exposure platform comprises locking members, cooperating elements for said locking members positioned adjacent said exposure platform, guide means provided in conjunction with said locking members on the walls of said housing which extend in the direction of the legs of the U-shaped path of travel of the copying paper, and a unit module including said surface element being supported and held within said housing by said guide means with said locking members and cooperating elements securing said surface element in position adjacent said exposure platform and being withdrawn from said housing through said one end wall thereof adjacent the vertically arranged portion of said U-shaped path of travel.
 4. A copying apparatus, as set forth in claim 3, characterized in that the walls for mounting said unit module including said surface element having centering profiles thereon and said unit module having corresponding mating profiles which extend in the direction of withdrawal of said unit module, and both sides of said unit module being provided with retaining levers with angled arms, and the walls mounting said unit module being provided with pins with which these angled arms cooperate by pivoting to lock said surface element in place.
 5. A copying apparatus as set forth in claim 4, wherein said arms have a wedge-shaped working surface and are of elastic construction, and are angled so that, when the closure is made, the levers pass beyond a dead center position.
 6. A copying apparatus including a housing; a charging device, an exposure device including an exposure plate for an original accessible on the outer surface of said housing and a unit including an exposure platform and a surface element cooperating with said exposure platform for positioning individual sheets of copying paper in an exposure station formed in said exposure device, a developing device with developing media, a fusing device, a stack holder for a stack of sheets of copying paper, and a delivery device for discharging developed sheets of copying paper from said housing being located within said housing; transport means within said housing forming a path of travel for conveying individual sheets of copying paper from said stack holder through said charging device, exposure device, developing device and fusing device to said delivery device; switching means for controlling said charging device, exposure device, fusing device and transport means and including actuating members adapted to be operated by an original passing over said exposure plate; wherein the improvement comprises that said housing comprises a plurality of openable covers for gaining access to the interior of said housing, said transport means comprising a number of pairs of rollers spaced along the path of travel of the sheets of copying paper within said housing, each said pair of rollers comprising a first roller and a second roller, each of said first rollers being secured within said housing and being spaced inwardly relative to its corresponding said second roller from the adjacent said openable cover in said housing; means within said housing for driving said first rollers; each of said second rollers being freely rotatable and movably mounted within said housing for displacement from the path of travel of the copying paper through said housing; said charging unit, surface element and developing device being separately removable through openings closed by said covers along with said second rollers so that access to the path of paper travel is attainable without removing said first rollers, the path of paper travel provided by said transport means has a U-shaped configuration with the legs of said U extending horizontally and the connecting web extending vertically, the upper leg of said U-shaped path of travel extending from said stack holder toward one end wall of said housing, the connecting web extending downwardly from said upper leg and adjacent said one end wall of said housing and the lower leg of said path of travel extending from the connecting web toward the other end wall of said housing to said delivery device, one of said covers being positioned in said housing above and adjacent to the upper leg of said U-shaped path of travel and said charging device and switching means being located aligned below the opening closed by said cover so that said charging device and switching means are accessible and removable through the opening, guide and abutment means being secured within said housing and being open at the upper ends thereof for supporting and securing said charging device and switching means within said housing, said one end wall of said housing adjacent the connecting web of said U-shaped path of travel having an opening therein closed by another of said covers which is hinged to said housing, said surface element of said exposure device being positioned adjacent said end wall and being removable through said hinged cover therein, means associated with said surface element for releasably engaging said surface element with said exposure platform, said developing device is a drawer-shaped unit module arranged with its inlet below the exposure platform, guide means are provided in said housing extending in the direction towards said cover through which said developing device is movable, and a roller arranged on the said unit module and a roller arranged on the platform form a pair of transport rollers leading into said developing device, and said developing device has outlet means downstream of which a pair of outlet transport rollers is arranged within said housing, and said developing device has a downwardly offset step behind said outlet means and one roller of said pair of outlet transport rollers is located within the said step.
 7. A copying apparatus as set forth in claim 6, wherein the apparatus contains a partitioning wall above the developing device, mounting means with springs being provided on the said partitioning wall carrying a roller, wherein the upper side of the developing device carries a friction wheel and driving means of the apparatus drive through transmission means the said roller and support with the said friction wheel the insertion of the developing device.
 8. A copying apparatus including a housing; a charging device, an exposure device including an exposure plate for an original accessible on the outer surface of said housing and a unit including an exposure platform and a surface element cooperating with said exposure platform foR positioning individual sheets of copying paper in an exposure station formed in said exposure device, a developing device with developing media, a fusing device, a stack holder for a stack of sheets of copying paper, and a delivery device for discharging developed sheets of copying paper from said housing being located within said housing; transport means within said housing forming a path of travel for conveying individual sheets of copying paper from said stack holder through said charging device, exposure device, developing device and fusing device to said delivery device; switching means for controlling said charging device, exposure device, fusing device and transport means and including actuating members adapted to be operated by an original passing over said exposure plate; wherein the improvement comprises that said housing comprises a plurality of openable covers for gaining access to the interior of said housing, said transport means comprising a number of pairs of rollers spaced along the path of travel of the sheets of copying paper within said housing, each said pair of rollers comprising a first roller and a second roller, each of said first rollers being secured within said housing and being spaced inwardly relative to its corresponding said second roller from the adjacent said openable cover in said housing; means within said housing for driving said first rollers; each of said second rollers being freely rotatable and movably mounted within said housing for displacement from the path of travel of the copying paper through said housing; said charging unit, surface element and developing device being separately removable through openings closed by said covers along with said second rollers so that access to the path of paper travel is attainable without removing said first rollers, the path of paper travel provided by said transport means has a U-shaped configuration with the legs of said U extending horizontally and the connecting web extending vertically, the upper leg of said U-shaped path of travel extending from said stack holder toward one end wall of said housing, the connecting web extending downwardly from said upper leg and adjacent said one end wall of said housing and the lower leg of said path of travel extending from the connecting web toward the other end wall of said housing to said delivery device, one of said covers being positioned in said housing above and adjacent to the upper leg of said U-shaped path of travel and said charging device and switching means being located aligned below the opening closed by said cover so that said charging device and switching means are accessible and removable through the opening, guide and abutment means being secured within said housing and being open at the upper ends thereof for supporting and securing said charging device and switching means within said housing, said one end wall of said housing adjacent the connecting web of said U-shaped path of travel having an opening therein closed by another of said covers which is hinged to said housing, said surface element of said exposure device being positioned adjacent said end wall and being removable through said hinged cover therein, means associated with said surface element for releasably engaging said surface element with said exposure platform, said delivery device includes a plug-in plate fitted in said housing which is adapted to be pulled out to provide access to the lower leg of the U-shaped path of travel, and one of said second rollers of at least one pair of transport rollers is mounted in the region of the delivery device on said plug-in plate and at least one said fixed driven first roller is arranged on the housing so that in the inserted position of said plug-in plate it makes contact with said second roller on said plug-in plate.
 9. A copying apparatus as set forth in claim 8, comprising at least two support rollers located in the zone of said delivery device on both sides of said housing, and said plug-in plate has angled flangEs guided on the said support rollers and at least one side of the opening from said delivery device is provided with a spring-loaded pawl having a locking element which engages in front of a side member of said housing at the opening.
 10. A copying device as set forth in claim 9, wherein guide grooves, open towards the center are formed on the underside of the plug-in plate, with a withdrawable slide plate mounted therein, and wherein the plug-in plate forms in this zone the bottom of the open housing. 